Electronic assembly with high capacity thermal spreader and methods of manufacture

Abstract

To accommodate high power densities associated with high performance integrated circuits, an integrated circuit package includes a heat-dissipating structure in which heat is dissipated from a surface of one or more dice to an integrated heat spreader (IHS) through a high capacity thermal spreader formed of diamond, a diamond composite, or graphite. In one embodiment, a diamond layer is grown on the IHS. In another embodiment, a diamond layer is separately formed and affixed to the IHS and/or to the die through soldering or through a room temperature surface activated bonding (SAB) process. Methods of fabrication, as well as application of the package to an electronic assembly and to an electronic system, are also described.

What is claimed is:  
     
       1. A method of fabricating an integrate circuit package, the method comprising: 
       affixing a layer of thermally conductive material to a lower surface of an integrated heat spreader (IHS), the material being from the group consisting of diamond, a diamond composite, and graphite;  
       mounting a die on a substrate, so that electrical contacts on a lower surface of the die are coupled to electrical contacts on an upper surface of the substrate; and  
       mounting the IHS over the die so that the thermally conductive material is in contact with the upper surface of the die.  
     
     
       2. The method recited in  claim 1  wherein affixing comprises: 
       growing the layer of thermally conductive material on the IHS surface.  
     
     
       3. The method recited in  claim 2  and further comprising: 
       forming a layer of metal on the IHS surface, the layer of metal being from the group consisting of chromium, gold, nickel, platinum, silver, titanium, tungsten, and vanadium.  
     
     
       4. The method recited in  claim 1  and further comprising: 
       growing the layer of thermally conductive material apart from the IHS surface.  
     
     
       5. The method recited in  claim 4  and further comprising: 
       forming a layer of metal on at least one surface of the layer of thermally conductive material, the layer of metal being from the group consisting of titanium and tungsten.  
     
     
       6. The method recited in  claim 1  wherein the IHS comprises a wall, the method further comprising: 
       coupling the IHS wall to the upper surface of the substrate.  
     
     
       7. The method recited in  claim 6  wherein the IHS wall is coupled to the upper surface of the substrate with a thermally conductive material. 
     
     
       8. A method of fabricating an integrate circuit package, the method comprising: 
       affixing a first surface of a thermal spreader layer to a surface of an integrated heat spreader (IHS), the thermal spreader layer being formed of material from the group consisting of diamond, a diamond composite, and graphite; and  
       attaching a surface of a die to a second surface of the thermal spreader layer.  
     
     
       9. The method recited in  claim 8  wherein affixing comprises: 
       attaching the first surface of the thermal spreader layer to the IHS surface using a surface activated bonding process.  
     
     
       10. The method recited in  claim 9  wherein attaching the first surface of the thermal spreader layer to the IHS surface further comprises: 
       forming a layer of metal on the IHS surface, the layer of metal being from the group consisting of chromium, gold, nickel, platinum, silver, titanium, tungsten, vanadium, and an alloy thereof.  
     
     
       11. The method recited in  claim 9  wherein attaching the first surface of the thermal spreader layer to the IHS surface further comprises: 
       forming a layer of metal on the first surface of the thermal spreader layer, the layer of metal being from the group consisting of chromium, gold, nickel, platinum, silver, titanium, tungsten, vanadium, and an alloy thereof.  
     
     
       12. The method recited in  claim 8  wherein attaching comprises: 
       attaching the surface of the die to the second surface of the thermal spreader layer using a surface activated bonding process.  
     
     
       13. The method recited in  claim 12  wherein attaching further comprises: 
       forming a layer of metal on the surface of the die, the layer of metal being from the group consisting of chromium, gold, nickel, platinum, silver, titanium, tungsten, vanadium, and an alloy thereof.  
     
     
       14. The method recited in  claim 12  wherein attaching further comprises: 
       forming a layer of metal on the second surface of the thermal spreader layer, the layer of metal being from the group consisting of chromium, gold, nickel, platinum, silver, titanium, tungsten, vanadium, and an alloy thereof.  
     
     
       15. The method recited in  claim 8  and further comprising: 
       before attaching, applying a thermal interface material to the surface of the die, or to the second surface of the thermal spreader layer, or to both the surface of the die and to the second surface of the thermal spreader layer.  
     
     
       16. A method of fabricating an integrate circuit package, the method comprising: 
       affixing a first surface of a thermal spreader layer to a surface of an integrated heat spreader (IHS), the thermal spreader layer being formed of material from the group consisting of diamond, a diamond composite, and graphite; and  
       attaching a surface of a heat sink to a second surface of the thermal spreader layer.  
     
     
       17. The method recited in  claim 16  wherein affixing comprises: 
       attaching the first surface of the thermal spreader layer to the IHS surface using a surface activated bonding process.  
     
     
       18. The method recited in  claim 17  wherein attaching the first surface of the thermal spreader layer to the IHS surface further comprises: 
       forming a layer of metal on the IHS surface, the layer of metal being from the group consisting of chromium, gold, nickel, platinum, silver, titanium, tungsten, vanadium, and an alloy thereof.  
     
     
       19. The method recited in  claim 17  wherein attaching the first surface of the thermal spreader layer to the IHS surface further comprises: 
       forming a layer of metal on the first surface of the thermal spreader layer, the layer of metal being from the group consisting of chromium, gold, nickel, platinum, silver, titanium, tungsten, vanadium, and an alloy thereof.  
     
     
       20. The method recited in  claim 16  wherein attaching comprises: 
       attaching the surface of the heat sink to the second surface of the thermal spreader layer using a surface activated bonding process.  
     
     
       21. The method recited in  claim 20  wherein attaching further comprises: 
       forming a layer of metal on the surface of the heat sink, the layer of metal being from the group consisting of chromium, gold, nickel, platinum, silver, titanium, tungsten, vanadium, and an alloy thereof.  
     
     
       22. The method recited in  claim 20  wherein attaching further comprises: 
       forming a layer of metal on the second surface of the thermal spreader layer, the layer of metal being from the group consisting of chromium, gold, nickel, platinum, silver, titanium, tungsten, vanadium, and an alloy thereof.  
     
     
       23. The method recited in  claim 16  and further comprising: 
       before attaching, applying a thermal interface material to the surface of the heat sink, or to the second surface of the thermal spreader layer, or to both the surface of the heat sink and to the second surface of the thermal spreader layer.